Planet gearing



June 17, 1930. c, KWLSEN 1,764,961

, PLANET GEARING e Sheets-Sheet 1 F1166 March 28, 1929 June 17,- 1930. c, rr'n s 1,764,961

PLANET BEARING 6 Sheets-Sheet 5 Filed March 28; 1929 IZ/Z worn/[Mean June 17, 1930. c'. KITTIL .SEN 1,764,961

PLANET GEARING Filed March 28, 1929 6. Sheets-Sheet 4 June 17, 1930. c, KlTTlLSEN 1,764,961

PLANET; GfiARING Filed March-28, 1929 'G'Sheets-Sheet 5 I Chant/W620,

[ n UenZo r.-

June 17, 1930. c, KlTTlLs 1,764,961

PLANET GEARING Filed; March 28'. 1929 6 Sheets-Sheet 6 ZZ E710 Count K666666620,

.1 nventfor:

a Cl.-. WQL J /7653 Patented June 17, 1930 UNITED srares PATENT o en 000M KITT ILSEN, 01 PO RSGRUND, NORWAY PLANET- GEABIIN G Application filed March 28, 1929, Serial 170,250,697, and in Germany February 25, 1928.

I have filed an application in Germany cross section on the line II-II of Figure 1. Feb. 25, 1928'. Figures 3 and 4 show another exam le of .The present invention relates to a planet construction for an automobile. gear, l igure gear particularly for power vehicles with a 3 being alongitudinal section and Figure 4 a a friction clutch which on the increase of load cross section on the line IV-IV of Figure 3. 55

onthe driven shaft permits the transmission Figures 5 to 9 illustrate a further form of ratio to be changed without it being necesconstruction-of'the. automobile gear accordsary for this purpose to engage or disengage ing to the invention, of which Figure .5 .is a any toothed wheels with or from other longitudinal section. Figure 6 is a section I w toothed members. Such a gear does not only on the line VIVI of Figure .5, Figure 7 is co have the advantage that when in use the tedia section on the line VIIVII of Figure 5, ous engagement and disengagement of FigureS, is a section on the line VIII-VIII toothed wheels and the dangers connected of Figure 5, and Figure 9 is a secti n on the therewith are eliminated, but the. change of line IX--IX of. Figure 5. 1'5. the transmission ratio is always effected so Figures 10 to 11 illustrate a gear suitable c5 that a vehicle fitted with such a gear can for motor cycles. Figure 10 is a longitudinal accelerate or. slow down without any shock. section and Figure 11 is a cross section on the .As compared with the gears of this'type line XL-XI of Figure 10. r hitherto knownthe present invention has t e The sections II-II, IV?IV and VIII- important improvement that the gear, with VIII are looking from left to right, the secm the exception'of changing into reverse or tions IXIX and XI-XI are lookin from using the motor as a brake, perates entirely right to left whilst the sections Vl-rl I and automatically, that is to say, without any VIIVII show the same view looking in actuation by the driver, that it is of comparaeither direction.

5 tively small dimensions and does not ossess In all the figures of the drawings'the part any sensitive parts subjected to rapi wear, fulfilling the same purpose are indicated by.

can easily be taken to pieces-andagaln re-asthe same references so as to facilitate thev sembled, and that finally it simultaneously understanding of their operations; serves the purpose of the usual clutch so that The-drum 2 according to Figures 1 and 2, is v 30 this in general may be omitted. for example connected to the engine shaft, Theessential feature .of ,the invention, by not shown, by the'clutchdisc 3, the clutch disc means of which, all these advantages are 0b 3 being preferabl at the same time formed as tained, resides in the fact that the two centhe fly-wheel. The 'drum2 is provided with tral .wheels, of which one is rigidly connected internal teeth 4' with which planet wheels 5 35 to the driving shaft, are formed as the inner mesh and wheels. .5 are connected to smaller toothed members of two concentrically toothed wheels 6 all being mounted on shafts mounted drums with which a gear planet 10. The toothed wheels 6 gear with the inwheels'of different diameter mesh, the comternal teeth 7 of a second drum 8 which ismon carrier of these planet wheels being freelyrotatable on the shaft. "9 connected to mounted on the driving shaft. 1: edriven wheels (not shown). Thev shaft 9 0 he lnve'ntion'will now be described With. wi in thedrums 2 and 8 is providedwith-an reference to the accompanying drawings in enlargement 11 provided,' 'i n the manner inwhich are shown fourexamples of construc- -dicated in-Figure 2-, with a window like apertion of the new gear, the first three examples ture '12. I Within this aperture 12 are located being suitable for' power vehicles, whilst the the toothed wheels 5 and 6. Their shafts 10" v" fourth isfor application of the invention to are rotatably mounted,in the manner indi -f a motor cycle. 1 cated in Figure 1, inthe discs 13 of the shaft Figures 1 and 2 show the first form of .conenlargement .12 which laterally limit the struction of an automobile gear, Figure 1 aperture 12. being a longitudinal section and Figure 2 a The drain-8 is provided with asleeve 1 shaped extension 14 the end of which is engaged by two nuts 26 screwed on the screwed -prt-i0n 25 of the shaft 9. The sleeve 14 is connected to a brake disc 15 which can be brought to rest by means of a band actuated by the foot or hand of the driver or by brake shoes 16.

The drum 2 is provided with a number of laminae 17 which co-operate with alternating and corresponding laminae 17 mounted on the hub of the drum 8. The outermost lamina bears a ainst a disc 19 of which the hub 22 is provi ed with an annular groove 21 accommodating a sprin 18 of which the 15 outer end disc 15 so normally pressed against brake disc 15 is axiallymovable'on the sleeve like extension 14 of the drum-8 by means of setting rings 20 screwed on to a screw threaded portion of thesleeve 14 so of the spring 18 and thus the pressure exerted on the laminae 17 17 can be suitably adjusted. The hub 22 of the disc 19 which receives in its annular groove 21 the spring 18 is in the known manner, and therefore only indicated diagrammatically, connected to a hand or foot lever 23 which when moved on its pivot 24 in the direction of the arrow moves the disc 19 against the pressure of the spring 18 away from the laminae 1 thus releasing the coupling between the two drums 2 and 8. acting as central wheels. The operation of the gear is as follows When starting the clutch 17, engaged in the manner above described by 'means of the foot or hand lever 23 and the engine is started so that the 'clutch disc 3 and the drum 2 connected thereto is set in rotation and the toothed wheels and 6 rotate on their shafts at a speed corresponding withthe ratio of reduction between the drum 2 and the wheel 5. As however, the shaft 9 with the two bear- 5 ing discs 13 of the planet gear 5, 6 has a braking action applied thereto by of-the vehicle these parts at first remain stationa'ry so that the wheels 5 and 6 driven by the drum 2rotate idly on their shafts 10. The

small toothed wheel 6, therefore, also drives the drum 8, which also rotates idly about the stationaryshaft 9, together with the sleeve 14 and the brake disc 15. As, however, the

wheels 6 are .at a her ratio to the drum 8 than the wheels 5 to-the drum 2, the drum 8 will rotate at a lower speed than the driving drum 2. If, however, the clutch 17 i 17" is firmly engaged by the action of the spring 18, the drum 8 will be directly driven by the drum 2 and at the same speed as this. The difierence in the transmission ratio be- -twe n"the toothed members 5 and' i on the oneha'nd and the toothed members 7 an on the other hand prevents the planet gear 5;i6;10, 13, 9 from turning.

' positive connection,

to one another by gear 5, 6, 10,

that the tension by means of the setting rings 17"; is disthe load and. the toothed members 6, 8 on freely in the drums 2 and 8. This planet gear is therefore compelled to rotate at the same speed as these thus forming a that is to say a transmission of 1:1 between the parts 3, 2 and 9 or between the driving sha and the driven shaft orthe wheels of the the speed at this moment is the hi hest.

If for any reason, for example w en'reaching an upward inclination, the resistance to travelling is increased then the'laminae 17 17 are caused to commence to slip relatively. the increased requirement of power whereby the drum 8 lags with a corresponding slip behind the drum 2 and the speed of the planet 13 with the-shaft 9 is reduced as it begins to roll in the drums 2 and 3 and thus 7 an increased torque is exerted on the vehicle wheels.

The tension of the spring 18 is 20- that the clutch only begins to slip when the normal engine load is exceeded.

From the foregoing it will be seen that the speed of rotation of the driven shaft 9, which drives the wheels of the vehicles, is always suitably adjusted between zero and the speed ofrotation of the engine whilst simul taneously varying in a suitable manner the torque exerted by the shaft 9 relatively to the amount of power required, and that'this not only takes placesconstantly, but also entirely automatically. Y

For the purpose of obtaining reversal. it is only necessary to disengage the clutch 17 17" b 'means of the g action-to the drum 8, by means of the which efiects the application of the shoes 16 drum 2 coupled with the engine to a greater extent than would correspond to the difierence of their, tooth transmission when run ning idly, so that the planet gears 5, 6, 10, 13, 9 are compelled to rotate in the opposite 'rec-' tion. The speed of this backward movement is naturally the higher the greater the braking action applied to the disc 15 and it reaches its maximum when the drum 8 is entirely stationary. In order to be able to effect the braking-act10n-15 smoothly it may be con- 7 nected to the drum';8 'or-to the sleeve 14 also by a laminae clutch.

By a suitable selection of the transmission ratio between the parts 2, 5 on the one hand the other hand it is possible even with a slight slippin of the lammae 17 17 or a slight relative difference in speed tween-the drums 2'and 8 to obtain a considerable variation in the speed vehicle of which so adjusted with the drums and.

an amount corresponding to lever 23 and to apply a brak- 7 that the laminae, which may consist alten' of rotation of the planet gear 6, 10, 13, 9 so nately of steel and another metal and may operate in an oil-bath, are only subjected to a s lght amount of wear. In order to effect engagement and disengagement as smoothly as.

possible a very large number of laminae is preferably employed. From the method of operatlon of this clutch 17 17" it will be seen that it renders the usual clutch between the driving shaft and the gear unnecessary.

Fromthe drawing and the specification it I willdae gsieh that the gear according to the present invention does not only permit of an entirely constant and. automatic variation of the ratio of transmission between the driven shaft and the driving shafts within the limits of 1: 1 to 1 00 but that b releasing the clutch- 17 17 which connects tlietwo central wheels 2 and 8 and by braking or stopping the drum 8 it is also possible to producer'earward movement when the same transmission ratio is constantly and automatically set up and corre- .sponds with the requiremenfof power at any time. By this simple change over to rearward. movement it is possible to exert a very intensive yet non-deleterious braking action. Even 1 though the teeth'of the gear are to some ex-' tent made strong it is possible, in the case of immediate danger, by lockin the drum 15 and disengaging the clutch 1 to allow the driven wheels of the vehicle to run backwardly without any undesirable strain being imposed upon the gear as would be the case with an ordinary change speed gear of which the toothed wheels would certain to brake if an attempt were made to reverse their di rection of rotation before they had come to I rest. With a gear according to the present invention however, in which it is not necessary 'to bring any of the toothed wheels into or out of engagement, it is impossible for this to occur.

Any number of lanet wheels5, 6 may be arranged around t e internal teeth4 and 6 in accordance withthe power to .be transmitted. For 1i ht vehiclesa single wheel 5,

.'6 is suflicient w ereas for heavier loads three or more such wheels may be necessary.

Although it has been previouslyassumed that the drum 2 or the clutch disc 3 was cont nected to the driving shaft and the shaft 9 of the lanet ear was connected. to the driven sha gear may be arranged in the reverse manner according to the present inventionf that is tosay the shaft 9 is connected to the engine and the drum 2 with the driven shaft, In this case a few slight constructional modifications, particularly in the selection of different transmission ratios may be preferable, but these. will not modify 4 tion and for this reason will not be further the scope of the invendescribed.

ll Figures} and4show a further construcwith the shaft 9.

or with the wheels of'the vehicle, the

tion of the gear according to the present invention, by which it is possible to use the en-.

gine for example when travelling down hill, as a brake and at a suitable time to lock some of the parts of the gear in such a manner that a definite transmission ratio is obtained, that is to say a transmission ratio which does not Var automatically with the variation of the using the engine as a brake, but also when travellin down steep inclines. In order to which is of advantage not only when obtain th1s result the form of construction of the gear shown in Figures 1 and 2 is modified.

The smaller wheels. 6 of the planet gear, in addition to engaging with the internal teeth 7 of th'ekdrum 8 may also engage with a common spur wheel 100 which is keyed to a sleeve 101 rotatabl and adjustably mounted onthe shaft 9 of the planet gear. This sleeve 101 can be clutched to the smaller drum 8 by means of a slipping clutch capable of being structiqn shown in Figure'l the two baring discs in this'case are connected together by a shaftportion 99 arranged concentrically On the sleeve 101 supporting the spur wheel 100 and freely rotatable onv the shaft 9 is mounted a disc 103 with a niimber of laminae 102*- which co-operate alternateiy with, cor-- respondin laminae 102 provided on the internal 'perlpher of the drum '8. To the outermost end of t e sleeve 101 is keyed a brake disc 107 by means of which the sleeve 101 and thus also the spur wheel can be braked or completely stopped, this being eifected by means of a brake band or, the like 104 actuated by a handlever or pedal. v

For this purpose the clutches 17*, 17!. and 102, 102 must be previously or simultaneously disengaged which may be effected by means of the operating lever 23 which acts on the drum 15 sub]ected to the pressure of the spring 18. Thedrum 15, \which in this example of construction at the same time serves the purpose of the disc 19 in Figure 1, is movable in grootes of the hub 14 of the drum 18, but is mounted so as to be prevented from rotating relatively to this and after disengaging the clutch .17, 17", by the brake band or the like 16 it can be braked in such a manner that the direction of rotation of the shaft 9 is reversedin the manner set out in .the description of Figures land 2. The tenand does not slip the driving shaft 9 is rigidly ti gonnectiom sion of the spring 18 is in this case, atso adand thus constantly they .vary the @transmisjustable by means of the nuts 20 which in this sion ratio between the driven shaft and the case are'fitted on the sleeve 101 and act upon driving shaft.- The spur wheel 100 connected the spring 18 by means of pins 105 which to the drumSby the slipping clutch 10.2,102 pass through the hub of the brake disc. Also and with the small planetqwh'eels 6' takes up 70 in this example of construction the arrangea portion of the transmission of power so ment is preferably such that the brake bands that the teeth of the pinions 6 which at the 16 1 accordin to selection, are P time are in engagement with the internal tively applied when isengaging the clutches te th"; are ub tantiall relieved of load 10 3 3 and y means of the p which is of advantage wli n the diameter iof 75 i g level I the wheel 6 or the number of teeth thereof is The. ge r 9. g to F gu 3 d kept as small as possible for certain reasons. operates as follows Finally'the dpuble engagement of the wheels when thefihltch 15 gg 6 also increases the static rigidity of the env so clutched to the driven shaft, which c rl' Thi'sgear by suitable selection of the trans spohds to hhehighest 'tlahslhlsslon l'atlo mission ratio may also be so arrangedthat the tween the (h'lvihg. and dnveh S e engine is connected to the shaft 9 whilst thevv sleeve 101 also rotates at the same speed tod i h ft-i o t d t th di 3 t -2 o g ther With he Wheel 1 key d thereto as the drum 2. Also withsuch an arrangement 5 w 45 greater the braldng a mum speed. If for anyreason the=resistance connected to the wheels 5 and 6 by a key and the sleeve 101 is connected'to the drum 8 by f the gear all the parts operate as a rigid; the clutch 102, 102". In this case no relative it as l as th l t h. 1:7 173 d not movement takes place between the toothed li A o h w y r, ny of th laminae members of the gears All the parts operate b i t ip h drums .2 d 9- l h hiha fls rigid Connection the transmission the planet wheels '5 and 6 or the bearing discs to ratio is 1:1. g 13 thereof and-reliitivelyto the shaft 9. For If itis now desired to use the .engineas the Purpose ofgfiflngiflg o er'to b ckward a brake it is only ne s ary by m v g th movement the drum am this case is also operating lever 23 n i pivot in the brakedby means of the disc and the band rection of the arrow against theaction of the, 16. The spur wheel '1O0mou1ited on the 95. 5 g 13 in Order to disengage the u ch sleeve 101 serves the same purpose in this 17b and thus also the clutch and case. In many casesthe arrangement of the simultaneously to brake the disc 107 with the gear in this manner has the advantage that l v 1 1 the Wh h Wheelsfi a more favourable speedratio is obtained and which were hitherto stationary on their th 1 s wear of the parts.

shafts 10'rotating in the beari g arms 13 3 The most complete construction of a gear now caused to roll on the Wheel Whlch particularly suitable for power vehicles acn w'l g behind the Shaft 9 is n y, cording to the invention is illustrated in 'Figwhergby the wheels 5 arevalso ro a $1151 ures 5 to'9. This construction not only posaccelera e th d um 2- thiSi'S connecteq t0 sesses the advantages of the construction ac- 1 the driving shaft by the disc 3 an' accelerat1on di to Fi 3 d 4 ith o id bl will also be imparted to the engine whereby smaller dimensions and fewer parts, but the pistons thereofwill act theknownm straining of the slipping clutch and also of 5 a brake, this 22 he Increased the the remaining parts of the gear is in this case v ion "PP ed to t disc reduced to a minimum. 1 no 107. The dr 8 is then slightly driven by In thi example of construction it is to be the rotating wheel 6 and runs ldly as th assumed that the shaft 9 supporting the clutches 17, 17 @1 23 1 are dlsenplanet gear-is connected to (the driving shaft gagedi whilst the central wheel 2 which gearswith AS50011 as the'chltch and thus also the larger planet wheel 5 by. means of the 'the clutch 102,-1 Mer -eng g and internalteeth therein is connected to the brake disc 107 has been r l s by releflsmgshaft 33-, which inthis case operates as the he b n 0 Wheel 100 15 c d. driven shaft and corresponds with theclutch the clutch 102, 02" to the dr m 8 a h 1S disc 3 of the previously described example of connected to the drum 2 by the clutch 17 17h construction. The drum 2 ma be coupled to so that all the parts area-gem m n 1 0n the shaft 33 by means of a key 40 or in any ne tion a e r th t is to y, h he othersuitable manner. In this example of transmission ratio is 1 1, when, as previously construction only asingle planet wheel 5, 6 stated, the vehicle is being driven at its maxi is provided of which the common shaft 10 105 to. travelling is increased the'clutch' 17, 17 groove, is mounted in an eccentri ore 34 of commences to more. or-less slip and the gear the shaft 9. The shaft 9 is providedwith two operates in the same manner as the arrange drum shaped enlargemntsQO and 900" each ment according to Figures 1 and 2 as the 4- of which is provided with'fia window-like 65 planet wheels-fi and 6 roll in the 2, 8 openin-g'91and901se'e Figuresig and 8). n

the reception of the planet wheels 5 and 6 respectively. The apertures 91 and 901 are limited by an are described about the centre of the shaft 10 so that the remaining portion of the'enlargement 90 or 900 has the shape of a sickle 92 or 902. In the left-hand end surface of the drum 2 are screwed the shafts 35 for two toothed wheels 37, which are loosely mounted on these shafts and gear with the internal teeth 36 of 'a druni 200 and with a toothed member 100 keyed to the shaft9, for which purpose thehub of the drum 2 is broken away at .two oppositely disposed points as will be clearly seen in Figure 6.

As long as.no relative rolling action takes place between the-teeth of the wheels 37. and the toothed member'36the drum 2, carrying the shafts 35 of the wheels 37, is rigidly connected to the drum 200, capable of being braked by the shoes or the like 104, which is provided with the laminae 17", of the slipping .clutch.

Differing fromthe two examples of constru'ction hereinbefore described the'laminae 17 in this case are located on the outer side of the drum 200, which is coupled with the larger wheel 5, whilst the laminae 17 are mounted on the inner periphery of the drum 15 provided with the smaller number of teeth 7, the end surface thereof being rigidly connected to'the drum 8, for example by screws At the end face of the drum 15 there are provided three bearings 39 (see Figure 9), preferably uniformly distributed around the circumference and receiving shafts 41 on each of which there are pivotally mounted bell crank levers 42. The outer end of these levers is provided with a screw thread into whlch are screwed set screws or the like 43, bearing against pins. 44 which are fitted into bores of the drum wall 15 and bear against a disc 55 which covers the laminae 17 or 17". The ends of the curved lever arts'42 engage by means of pins 45 er the ike in the annular groove47 of a bush 46 having on its periphery an annular rib 48. I

The rib 48 engages with a corresponding annular groove in a ring 50 pivotally connected at 52 to the operating lever 23 and by rockingthe latter on its pivot 24 can be moved in an axial-dire 46 rotating therewith. The outer end of the bush 46 is provided with an internal screw thread into which is fitted a lock nut 49 against the rear end surface of which bears a spring 18 which presses against the drum 8 and is located in an annular recess 21 of the drum 8. The front end surface of the nut 49 is provided with slots 51 for'the engagement of pins on, a spanner for the pur ose of enabling the nut to be adjusted relatlvely to the bush 46 for the purpose of varying the tension of the spring 18. By locking the lever 23 in ction when it moves the bush the nut 49 screwed therein are moved akially against the pressure of the spring 18, whereby the three double levers 44 controlled by the bush are swung about their shafts 41 in a clockwise direction and are raised from the pins 44 as a result of which "the laminae clutch 17, 17 is released.

In so far as the method of operation of this form of construction has not already been set outrin the foregoing, it will now be de-- scribed.

. a As long as the load oil the gear is not so" large that the laminae 17 and 17 commence to slip-relatively all the parts form a rigid connection,-that is to say a transmission ratio ofll :1. As soon however on the increase of load a slipping occursin the slippin clutch member 100, drive t e drum 200 which runs idly. The planet wheel 5 mounted on the shaft 10 in the engine shaft 9 rolls on' the internal teeth 4 of the stationary drum 2, its speed of rotation being abovethe speed of the engine. As the wheel 6, rigidly cou- .90 shafts 35-under t e action" of the toothed pled to the larger planet wheel 5 by means of the shaft 10 is in a. difi'erent. relation to the drum 8 than 'the'planet wheel 5 to the drum 2, the drum 8 rotates idly. about the engine shaft 9. If however-the clutch 17, 17 is slowly engaged the drum 8 is gradually driven shaft 33'by means of 'coupledto the 37, 2,40 and'a load correthe parts 200, spondingly applied thereto of rotation is reduced. This causes a lagging of the wheels 5 and 6. As however the engine shaft continues to rotate at a constant -speed the large planet wheel 5 is now caused so that its speed to drive the drum 2 and the driven shaft 33 i .at a lower speed, but with a higher torque.

The spur wheels 37 mounted in the drum 2 1n this case rotate around the toothed member 100 of the engine shaft 9, whilst they transmit a portion of the effective torque di rectly from the shaft-9 or the toothed member 100 to the drum '2 and in this manner partly relieve the load from 5,6, 7. Thewheels 37 which rotate about their shafts 35 and simultaneously roll around thetoothed member 100 exert through the drum 200, the laminae 17 17 the drum 8- and the teeth 7, 6 a torque which tends to oppose the torque of the engine shaft 9 according to the degree of reduction between the drum-8 and the engine shaft.

As its force howeverexerts a reaction'on the shafts 35 of the wheels 37 and thus also the planet gear 4,

as 7 between the teeth 100,37, 36.

17" has been completely on the drum 2 and the driven shaft 33, pracit is only necessary to I below the speed of idle running.-

to. rotate I 107 in Figure 3, is

- rupted and the drum-200 is brake tically no ener When chang iiig is lost.

over to reverse movement release the clutch 17", 17 'and at the same time to brake the disc 15 by means of the shoes or -the like 16 so, that the drum 8 .is brought to rest -or is braked to a determined period of rotation which is In this. manner the drum 2 is caused by the planet gear, in the mai i ner. hereinbefore described,

in the opposite direction. Ifjtgs desired to use the engine as a brake theijr whilst simultaneouslyreleasing the clutcll' 17, 17 the drum 200'is braked by means of the shoes or the like 104, whereby the planet wheels are entirely relieved of load and a constant transmission ratio is set up by the teeth 100 and 37 tbetween the parts 33, 2 and the engine shaft 9 which is only de-. pendent upon the degree-of slipping between the brake shoes 104 and the drum 200 but no n the load of the longer, as previously, upo gear. If the at the same time serves the purpose of the disc braked until it comes to of the-shafts 33 and rest then the speed ratio diameter 6 9 is now only dependent upon the ratios of the teeth 100 and 36. I

If at a given moment with a suitable speed ratio between the shafts 3 and 9 the supply of fuel or, the i 'tion of the engine is interd while simultaneously releasing the clutch 17', 17"

. then, if it is assumed that the diameters 'of the teeth 100 and 36 are in the propor-' tionof 1: 3, the engine is accelerated correspondingly by the driven shaft, which contween the laminae 17 energy of travelling, 'inthe known -manner tinues to rotate under the action of the kinetic whilst the engine acts as a brake to a high degree. By gradually tighteningthe shoes 104 the braking action can be produced substantially more smoothly.

Also in this gear the adjustment of a definite transmission ratio, that is to say a transmission ratio which is independent of the load upon the gear, is of considerable value not only when using the engine as a brake but in many cases fduring normal travelling, particularly when overcomi g considerable gradients as it may become overload the engine transmission ratio. In comparison with the examples of construction hereinbefore described, the gear according to Figures 5 to 9 has the advantage that the speeds of rotation of the toothed wheels are lower, thus reducing wear and noise and increasing the efliciency. 'Also in this example of construction the slipping beand 17 is reduced to a Even an. extremely small slipping'ofthe slipping clutch lead toza very,

drum 200; which in thiscase considerable variation in the t nsmission ratio.

The assemblage of the gear is efiected in the following manner: v

. First the stepped wheels. 5 and 6 are inserted into the openings 91 and 901, whereupon the shaft 10 is introduced through the bore 34 of the shaft 9 and is the bores of the 1planet. wheels 5' and 6. The wheels are then eyed key 106 (Figures 7 and 8). The drum 10 is then fitted on the shaft 9 whereupon the spur wheels 37 are mounted in position on the shafts 35. The smaller drum 8 is now passed over the planet wheel 6 and the drum 200 is passed over the drum 8 so that the internal teeth 36 thereof enga e The laminae 17 and 1 are fitted intoposition alternately and the drum 15 passed over these, this drum being then conn ted-to the drum 8 by means of the screws 38. Finally the spring 18 is placed into the anular groove 21 o the drum 8 sary to place in position the double arms 42 with the bush 46 and the locking nut 48.

It may be mentioned. that the slipping clutch 17 17" need not necessarily be located between the two central wheels 2 and 8 or 200 and 8, but may also be located between the engine shaft and the larger central wheel..

Such an arrangement of the slipping clutch has the advantage that it only has to transmit the torque derived from in the examples of construction illustrated and described it has to take up the increased torque due to the transmission.

The example of construction for bicycles and the like illustrated Figures 10 an is naturally of more simp The disengageablefslipping clutch is in this case replaced by a spring'disc or the like subjected to the action of one or two lock nuts.

On the shaft 3, carrying the pedals (not shown), is keyed the disc 2 with internal teeth 4, serving the purpose ofthe large central wheel, with which larger planet wheel 5. The connected to this wheel .5 is rotatably mounted in the, hub member 9 and carries at its other end the smaller wheel 6, whichis keyed thereto and meshes with the internal teeth 7 of a second disc 8 against the outer end surface of which bears the spring disc or the like 17. The pressure of th 17 is adjustable by means'of the lock nuts 20 engaging with he screwed portion 25 of the shaft 3, "The hub body '9, which is mounted in the known maner in a ball bearing 54,-only indicated diagrammatically,carries a chain wheel 53 by means of which to the shaft 10 by the e spring disc the guided through v with the wheels whereupon it is'onlyneces-- the engine, whereas Y power can be transmitted to the hub of the 110 teeth meshes the shaft 10 rigidly described. The driving force is transmitted through the planet If the resistance to travelling exceeds a I predetermined amount the disc 8 will more of construction of the invention the transmis-v sion ratio betweenone planet wheel and its j or less slip on the shaft 3 relatively to the spring disc 17 whereby the speed of the planet geaFrelativel to the shaft 3 is reduced and the torque acting on the hub 9 or on the chain wheel 53 is correspondingly increased.

It may be mentioned that in all file forms corresponding internal teeth must be different to the transmission ratio of the other P18111181, wheel and its corresponding internal teet Although the new gear has been described malnly in connection with vehicles it will be adapt the speed of rritation scribed, a

understood that the present invention. is not.

limited to this application. The invention is also applicable with advantage to stationary plants where, for example, it is necessaryto of a shaft under load to the'load acting thereon at any time without the driving motor being subjected to load variations at a given speed.

I claim 1. In a planet gear for the purpose vdedriving shaft, a driven shaft, a pair of internally toothed drums having different numbers of teeth, one of said'drums being secured to one of said shafts, a carrier on the other of said shafts, a-pair of pinions of different diameter mounted in said carrier to rotate together and of" said drums, yieldable the drums and pinions to unit so as to give direct transmission or automatically operable to, permit partial relative movement of said drums and gears upon an overload so as toivary the ratio of transmismoupted in said carrier to .rotate together and the, com

2. In a planet gear as claimed in claim 1 said yieldable means including a clutch and resilient means for normally holding said clutch in engaged position, said resilient means permittingv saidiclutch to slip upon an overload.

ination with. a driv1ng member an a driven member, of a pair of internally toothed drums, the number of teeth being different in the two dru'ms, one of said drums being rigidly connected to one of said members a carrier mounted on the other member, and a pair of planet wheels of different diameter planet gear for the purpose described gearing with the internal teeth of said drums,

(tbothedj-wheels rotatabl mounted -on the havlnglarger num er of teeth, gear tootheddrums, the number of teeth ferent in the two drums, one of said drumsengaging the teeth means for causingrotate together as a I ber of teeth, a ear wheel mounted on-the the carrier is mounted and .for cooperating with said of the gear is obtained.

1 member,

carrier is mounted a toothed wheels,

(1 gearing with said a third drum surrounding" the drum having the smaller number of internal teeth, said third drum having internal teeth with which the 'said toothed wheels enthird drums. A

4. In planet gear for the purpose described, the combination with a driving memberand a driven member, of a pair of internall' being di being rigidly connected to one of said members, a carrier mounted on the othe r'member, and a pair of planet wheels of different diameter mounted in said carrier to rotate together and gearing with the-internal teeth of gage, and a clutch between the sdcond and said drums, toothed wheels rotatably mounted.

on the drum having a larger number of teeth, a gear wheel mounted on the member on 1 mounted-and gearing which-the carrier is n with said toothed wheels, a third drum surrounding the drum having the smaller number of internal teeth, said third drum liav-f ing' internal teeth with which the said toothed wheels engage, and a clutch betweenthe second and third drums, said third mentioned -.d rum including a brake disc, and braking means cooperating with said brake disc.

5. In planet gear for the purpose de-;, scribed, the combination with a driving mem ber and a driven member, of a pair 0 inter; nally toothed drums, the number of teeth being difler'ent in the two drums, one of said drums being rigidly connected to one of said members, a carrier mounted ,on the other member, and a pair of planet wheelsof-dif- .ferent diameter mounted in said carrier to rotate together and gearing with the internal teeth 0 said drums, toothed wheels rotatably mounted on the drum' having a larger numby when a brakin action is applied to the brake a reversal o the directionfof rotation In a planetggear for the-purpose described, the combination with a drivin memthird brake disc, wherei ber and a drivenmeinberfof a pair 0 internally tootheddrums, the number of teeth-being diflerent in the two drums, dne of said drumsbeing rigidly connected to one of said members,

a carrier mounted on the other,

anda pair of planet wheels ofdif 'ferent diameter mounted in saidcarrier to rotate together and gearing with the internal use - ly connected to drum surroun drums,

said third drum having teeth of said drums, toothed wheels rotat-' ably mounted on the drum having a larger number of teeth, a gear wheel mounted on the member onwhich the carrier is mounted and gearing with said toothed wheels, a third having the smaller number of internal teeth, said third. drumhaving internal teeth with which the said toothed wheels engage, and a clutch between the.sec0nd and third drumsg and means for braking said second drum.

7. In planet gear for the purpose described, the combin tion with a driving member and a driven member, of a pair of internally toothed the number of teeth being one of said drums being rigidone of said members, a carrier mounted on the other member, and a pair of planet'wheels of difierent diameter mounted in saidcarrier to rotate together and gearing with the internal teeth of said drums, toothed the two drums,

wheels rotatably mounted on the drum having a larger number of teeth, a gear wheel mounted on the member on WhlCh the carrier is mounted and earing withsaid toothed wheels, a third rum surrounding the drum having the smaller number of internal teeth, internal teeth with which the said toothed wheels enga e, and a 30- I and means for braking clutch between the second and thir drums,

two of said drums.

In testimony whereof I afiii; g iK signature.

' COOM ILSEN;

difierentin 

